I have a problem with drivers on arch linux. I installed catalyst through unnoficial catalyst repo as wiki says.

pacman -S catalyst catalyst-utils
aticonfig --initial

After this operation i rebooted the system. KDM loaded succesfully, but when i tried to switch to console (ctrl+alt+1/2/3) i saw only some strange dots, like pixels from the text were splitted on the whole screen. I was able to go back to kdm and enter the account details tho. This gave me a hang just before kde loaded. Here's a video where i'm showing above actions. Anybody knows what caused the problem? I can still chroot to fix some issues. Thanks for interest.

Ok, i found a sollution, so i'm posting if someone else shares my problem. Catalyst does not support KMS, so you need to disable it from grub. You must know where are your /etc and /boot paritions mounted. If you have only one partition for / it's even simplier. Mount / on /mnt

mount /dev/sdaX /mnt

where X is number of the partition where is your / installed

arch-chroot /mnt
nano /etc/default/grub

and add line:

GRUB_CMDLINE_LINUX="nomodeset"

save and quit
then run (this will delete your windows grub configuration)